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POOpenCV: assertation failed ((img.depth() == CV_8U || img.depth() == CV_32F) && img.type() == templ.type())
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copied!<p>I get this error from above and don't know how to avoid it. My aim is to get a screenshot and then perform a template matching on it to see if an icon is shown on the screen at this moment. Till now it's just the position of the icon. My code:</p> <pre><code>#include "opencv2/highgui/highgui.hpp" #include "opencv2/imgproc/imgproc.hpp" #include "opencv2/core/core.hpp" #include <Windows.h> #include <iostream> #include <stdio.h> #include <string> using namespace std; using namespace cv; Mat hwnd2mat(); /// Global Variables Mat img; Mat templ; Mat result; int main() { /// Load image and template templ = imread( "Template.bmp",1); templ.convertTo(templ, CV_8U); //img = imread( "Image.jpg", 1 ); img = hwnd2mat(); /// Create the result matrix int result_cols = img.cols - templ.cols + 1; int result_rows = img.rows - templ.rows + 1; result.create( result_cols, result_rows, CV_8U); /// Do the Matching and Normalize matchTemplate( img, templ, result, CV_TM_SQDIFF ); normalize( result, result, 0, 1, NORM_MINMAX, -1, Mat() ); /// Localizing the best match with minMaxLoc double minVal; double maxVal; Point minLoc; Point maxLoc; Point matchLoc; minMaxLoc( result, &minVal, &maxVal, &minLoc, &maxLoc, Mat() ); /// show best position matchLoc = minLoc; cout<<matchLoc<<" is best position"<<endl; waitKey(0); return 0; } Mat hwnd2mat(){ HWND hwnd = GetDesktopWindow(); HDC hwindowDC,hwindowCompatibleDC; int height,width,srcheight,srcwidth; HBITMAP hbwindow; Mat src; BITMAPINFOHEADER bi; hwindowDC=GetDC(hwnd); hwindowCompatibleDC=CreateCompatibleDC(hwindowDC); SetStretchBltMode(hwindowCompatibleDC,COLORONCOLOR); RECT windowsize; // get the height and width of the screen GetClientRect(hwnd, &windowsize); srcheight = windowsize.bottom; srcwidth = windowsize.right; height = windowsize.bottom/1; //change this to whatever size you want to resize to width = windowsize.right/1; src.create(height,width,CV_8U); // create a bitmap hbwindow = CreateCompatibleBitmap( hwindowDC, width, height); bi.biSize = sizeof(BITMAPINFOHEADER); bi.biWidth = width; bi.biHeight = -height; //this is the line that makes it draw upside down or not bi.biPlanes = 1; bi.biBitCount = 32; bi.biCompression = BI_RGB; bi.biSizeImage = 0; bi.biXPelsPerMeter = 0; bi.biYPelsPerMeter = 0; bi.biClrUsed = 0; bi.biClrImportant = 0; // use the previously created device context with the bitmap SelectObject(hwindowCompatibleDC, hbwindow); // copy from the window device context to the bitmap device context StretchBlt( hwindowCompatibleDC, 0,0, width, height, hwindowDC, 0, 0,srcwidth,srcheight, SRCCOPY); //change SRCCOPY to NOTSRCCOPY for wacky colors ! GetDIBits(hwindowCompatibleDC,hbwindow,0,height,src.data,(BITMAPINFO *)&bi,DIB_RGB_COLORS); //copy from hwindowCompatibleDC to hbwindow DeleteObject(hbwindow); DeleteDC(hwindowCompatibleDC); ReleaseDC(hwnd, hwindowDC); return src; } </code></pre> <p>The function with the screenshot is not my own work, i got it from <a href="https://stackoverflow.com/questions/14148758/how-to-capture-the-desktop-in-opencv-ie-turn-a-bitmap-into-a-mat">here</a></p> <p>Any Ideas what to do?</p> <p>Thanks for help, best regards!</p>

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